ugh, I was really hoping more people would participate in this....not an artist, by any stretch of the imagination, but I love well-drawn fakemon...and i'm extremely curious how Fennekin's final evo will turn out. and shoutout to /u/legit_zurg for his awesome drawing, even though it's the only one :(

Thanks for the compliment! I have been busy but I finally managed to touch it up and color it. I edited my comment with the new link if you're interested. Wish this thread would've taken off too. I love this kind of thing.

Fennekin's evolution is Fire/Psychic. It would look unusually like the original evolution, but the size of the standard third form, meaning that it would be a fennec fox with a massive disproportionate head, and flames coming off behind the ears as if the brain was overheating. It would probably be at least somewhat emaciated, but not grossly so. Sort of like Mew in its proportions.

Chespin's evolution is Grass/Dark, and is based off a porcupine. I'd predict that the spines, resembling horns, would be going off the back and down the arms. Though that might seem to lend itself more towards Fighting, remember that Dark is less abut a lack of light than it is about cruelty and meanness. The head would probably look a bit like Typhlosion in structure and proportion. The torso would probably be pretty thick, like Emboar.

Froaky's evolution would be Water/Fighting, and though it seems a bit unlikely that it'll actually happen, I'll predict that it will be based on Benjamin Franklin like Empoleon was based on Napoleon. Many of the features (the ruff, the hair, the spectacles) have already been established on Froaky, as well as the location of the region being appropriate, because BF was ambassador to France, but the link will be even more obvious when it stands upright, as would be appropriate for a fighting type. I think it will either have claws, like the Xenopus Lavis, or have large webbed hands to slap with. The only issue for the latter is that BF historically went to France to meet prostitutes, and judging by the apparent location of the new game, slapping might seem a bit distasteful.